Method for producing 2-(triazinylcarbonyl) sulfonanilides

ABSTRACT

The present application relates to a process based on the oxidative ring opening of a compound with oxindole structure for preparation of substituted 2-(triazinylcarbonyl)sulfonanilides of the formula (1-1) proceeding from N-sulfonyl-substituted 3-triazinyloxindole of the formula (2-1), and to the 2-(triazinylcarbonyl)sulfonanilides of the formula (1-1) thus prepared, and to the use thereof as intermediates for the synthesis of fine chemicals and of active ingredients in the agricultural sector. 
     The invention also relates to a multistage process for preparation of N-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides of the formula (4-1), proceeding from a 3-(alkylsulfanyl)-1,3-dihydro-2H-indol-2-one of the formula (7-1), wherein the multistage process also comprises, as a component step, the oxidative ring opening mentioned, and to the 2-(triazinylcarbonyl)sulfonanilides of the formula (1-1) which are obtained by the oxidative ring opening and are used as intermediates in the multistage process.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a §371 National Stage Application ofPCT/EP2011/073287, filed Dec. 19, 2011, which claims priority toEuropean Application No. 10196205.8, filed Dec. 21, 2010; U.S.Provisional Application No. 61/425,349, filed Dec. 21, 2010; EuropeanApplication No. 11159875.1, filed Mar. 25, 2011; U.S. ProvisionalApplication No. 61/467,598, filed Mar. 25, 2011; and German ApplicationNo. 10 2011 086 382.6, filed Nov. 15, 2011.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present application relates to a process based on the oxidative ringopening of a compound with oxindole structure for preparation ofsubstituted 2-(triazinylcarbonyl)sulfonanilides of the formula (1-1)proceeding from N-sulfonyl-substituted 3-triazinyloxindoles of theformula (2-1), and to the 2-(triazinylcarbonyl)sulfonanilides of theformula (1-1) thus prepared, and to the use thereof as intermediates forthe synthesis of fine chemicals and of active ingredients in theagricultural sector.

DESCRIPTION OF RELATED ART

The invention also relates to a multistage process for preparation ofN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides ofthe formula (4-1), proceeding from a3-(alkylsulfanyl)-1,3-dihydro-2H-indol-2-one of the formula (7-1),wherein the multistage process also comprises the oxidative ring openingmentioned as a component step. The intermediates used in the multistageprocess, as well as the 2-(triazinylcarbonyl)sulfonanilides of theformula (1-1), are also triazinyl-substituted oxindoles of the formula(5-1) and N-sulfonyl-substituted 3-triazinyloxindoles of the formula(2-1), the subject-matter of the present invention likewise includingtriazinyl-substituted oxindoles of the formula (5-1) andN-sulfonyl-substituted 3-triazinyloxindoles of the formula (2-1), andthe use thereof as intermediates for the synthesis of fine chemicals andof active ingredients in the agricultural sector.

It is known that sulfonanilides can have herbicidal activity (WO93/09099, WO 96/41799, WO 2005/096818, WO 2007/031208 and US2009/0062536) or fungicidal activity (WO 2006/008159).

The sulfonanilides with herbicidal or fungicidal action disclosed in theprior art also comprise the 2-(triazinylcarbonyl)sulfonanilides as asubgroup.

According to the prior art, 2-(triazinylcarbonyl)sulfonanilides can beprepared by various routes. However, the processes known from the priorart for preparation of 2-(triazinylcarbonyl)sulfonanilides do not havethe aim of performance of the reaction on the industrial scale.

The document US 2009/0062536 describes the preparation of a substituted2-(triazinylcarbonyl)sulfonanilide A1, as summarized in scheme 1.

In the process according to scheme 1, the substituted2-[(methylsulfanyl)(1,3,5-triazin-2-yl)methyl]aniline A4 is reduced withnickel chloride hexahydrate and sodium borohydride to give a2-(1,3,5-triazin-2-ylmethyl)aniline A3 (synthesis example 13 in US2009/0062536). This process is sulfonylated to give anN-[2-(1,3,5-triazin-2-ylmethyl)phenyl]alkanesulfonamide A2 (synthesisexample 15 in US 2009/0062536). This is followed by oxidation with fourequivalents of chromium(VI) oxide to give the desired product A1(synthesis example 17 in US 2009/0062536). The yield of the oxidationdisclosed in US 2009/0062536 is 15%.

The use of the process according to scheme 1 on the industrial scale hasthe disadvantage that the carcinogenic reagents chromium(VI) oxide andnickel chloride hexahydrate have to be used in excess, and still onlysmall yields are achieved.

In addition to the disadvantages mentioned in the process regime of thepreparation route described in scheme 1, it should be emphasized thatthe preparation of the2-[(methylsulfanyl)(1,3,5-triazin-2-yl)methyl]aniline A4 used as thereactant in scheme 1 is also costly and inconvenient. The preparation ofreactant A4 is likewise described in US 2009/0062536 (synthesis example7 in US 2009/0062536). For this purpose, a substituted aniline isreacted with tert-butyl hypochlorite and2-[(methylsulfanyl)methyl]-1,3,5-triazine.

However, the industrial use of this process has the disadvantage that itis necessary to use the explosive tert-butyl hypochlorite as a reagent.

Moreover, the 2-[(methylsulfanyl)methyl]-1,3,5-triazine used is asynthesis unit whose preparation proceeds over several stages and whoseuse is therefore disadvantageous for industrial applications.

The preparation route shown in scheme 1, more particularly the oxidationof N-[2-(1,3,5-triazin-2-ylmethyl)phenyl]alkanesulfonamides (seecompound A2 in scheme 1), is also described by similar synthesisexamples in further documents (WO 2007/031208, WO2006/008159 andWO2005/096818A1).

The process disclosed in WO 2007/031208 is shown in scheme 2. This is analternative process to the process shown in scheme 1 for preparation ofsubstituted 2-(triazinylcarbonyl)sulfonanilides.

According to WO 2007/031208, anN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(methylsulfanyl)methyl]phenyl}methanesulfonamideB2 is stirred with potassium carbonate and iodomethane in a solvent for48 hours, and then the desired product B1 is isolated (reference example2 in WO 2007/031208).

However, the yield is only 57.5%.

Moreover, the use of the process shown in scheme 2 on the industrialscale has the disadvantage that the oxidation of B2 to B1 is alwaysaccompanied by an alkylation on the nitrogen, and therefore it is notpossible to directly obtain a compound not alkylated on the nitrogen bythis route. The methyl iodide used as the alkylating agent is alsoproblematic from a technical point of view due to its high vaporpressure and toxicity. Moreover, the long reaction time is alsodisadvantageous.

The practicability of the preparation of theN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(methylsulfanyl)methyl]phenyl}methanesulfonamideB2 used as the reactant in scheme 2 is shown in WO 2007/031208 not usingthe example of the triazine compound (X═N), but only using the exampleof a pyrimidine compound (X═CH), as summarized in scheme 3.

In this case, a substituted aniline is reacted with tert-butylhypochlorite and 2-[(methylsulfanyl)methyl]pyrimidine, and a2-[(4,6-dimethoxypyrimidin-2-yl)(methylsulfanyl)methyl]aniline C3 isobtained as an intermediate (synthesis example 10 in WO 2007/031208).This compound is sulfonylated to give anN-{2-[(4,6-dimethoxypyrimidin-2-yl)(methylsulfanyl)methyl]phenyl}methanesulfonamideC2 (synthesis example 9 in WO 2007/031208). The yield of thesulfonylation is only 27%.

Tables 5 and 6 of document WO 2007/031208 also list examples ofN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(methylsulfanyl)methyl]phenyl}methanesulfonamidesB2 or2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(methylsulfanyl)methyl]anilineswhich have been prepared in a similar manner to C2 and C3.

However, the industrial application of the process shown in scheme 3 hasthe disadvantage that it is necessary to use the explosive tert-butylhypochlorite (BuOCl) as a reagent, and the yield in the sulfonylationreaction is low. Furthermore, the 2-[(methylsulfanyl)methyl]pyrimidineused is a synthesis unit whose preparation likewise proceeds overseveral stages and is therefore disadvantageous for industrialapplication.

In another previously known process for preparation of substituted2-(triazinylcarbonyl)sulfonanilides, the oxidation to give the desiredproduct is performed with hydrogen peroxide. For instance, the documentUS 2009/0062536 already cited describes the preparation ofN-{2-[(4,6-dimethoxypyrimidin-2-yl)carbonyl]phenyl}alkanesulfonamides D1fromN-{2-[(4,6-dimethoxypyrimidin-2-yl)(methylsulfanyl)methyl]phenyl}alkanesulfonamidesD2 by oxidation with hydrogen peroxide in glacial acetic acid (seesynthesis examples 3, 4 in US 2009/0062536), as summarized in scheme 4.

Tables 2 and 3 of document US 2009/0062536 also list examples ofN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]phenyl}-N-alkylmethanesulfonamidesE1 (i.e. X═N) which have been prepared in a similar manner to D1 andalways contain an alkyl radical on the nitrogen (see scheme 5 below).

In this process, it is necessary to useN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(methylsulfanyl)methyl]phenyl}methanesulfonamidesE2 as reactants, the preparation of which on the industrial scale hasthe disadvantages described above. The oxidation reaction in thisprocess takes place on the sulfur at first. Under the acidic reactionconditions, the hydrolysis then proceeds to give the ketone. Thepresence of an oxidizable sulfur substituent is therefore a necessaryprerequisite for the process.

However, it is not evident from document US 2009/0062536 whether2-(triazinylcarbonyl)sulfonanilides which have not been alkylated on thenitrogen can also be prepared by this process. It is also unclearwhether the oxidation reaction to give these compounds is performablewith hydrogen peroxide, since chromic anhydride was used as theoxidizing agent in the use examples executed in US 2009/0062536, inwhichN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]phenyl}-N-alkylmethanesulfonamideswere prepared (see synthesis examples 17, 18 in US 2009/0062536).

WO 2007/031208 also mentions the possibility of preparation ofN-{2-[(4,6-dimethoxypyrimidin-2-yl)carbonyl]phenyl}alkanesulfonamides byoxidation with hydrogen peroxide. In the use examples executed forpreparation ofN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]phenyl}methanesulfonamides,the oxidation is, however, performed exclusively with chromium(VI)oxide.

Thus, the aforementioned processes known from the prior art have thedisadvantage that, for the reasons mentioned above, they are only oflimited suitability for preparation of2-(triazinylcarbonyl)sulfonanilides on the industrial scale due to thedisadvantages mentioned.

In the search for an industrially usable process for preparation of2-(triazinylcarbonyl)sulfonanilides, it was first recognized in thecontext of the present invention that(N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides couldpossibly be prepared from N-sulfonyl-substituted 3-triazinyloxindoles bythe oxidative ring opening shown in scheme 6a.

In terms of the general principle, the oxidative ring opening of3-phenyl-1,3-dihydro-2H-indol-2-ones to(2-aminophenyl)(phenyl)methanones is known. It is likewise known thatthe oxidation can be effected with oxygen or with hydrogen peroxide.

For instance, the oxidation of1-methyl-3-phenyl-1,3-dihydro-2H-indol-2-one with oxygen in the presenceof cobalt catalysts is disclosed in the scientific publicationHeterocycles, 1982, 2139, the main product of the oxidation being thedimer of the reactant, namely 2-methylaminobenzophenone. Another productformed is a (2-aminophenyl)(phenyl)methanone, but in only a small yield,namely at 2% to 6%.

Document U.S. Pat. No. 4,021,469 discloses the oxidation of3-phenyl-1,3-dihydro-2H-indol-2-ones with oxygen in the presence ofsodium methoxide in methanol. The methyl carbamates are formed at first,and are then cleaved in a second reaction step after addition ofpotassium hydroxide or water, as a result of which sodium hydroxideforms, by heating under reflux for several hours to give(2-aminophenyl)(phenyl)methanone. However, these conditions (see example4 in U.S. Pat. No. 4,021,469) are unsuitable for the conversion of3-(1,3,5-triazin-2-yl)-1,3-dihydro-2H-indol-2-ones, since the triazinering would be cleaved hydrolytically.

The oxidation of 3-hydroxy-3-phenylindolin-2-ones by means of hydrogenperoxide is described in J. Chemical Soc., 1959, 2366. The reactantsused are prepared by addition of the phenyl Grignard compound orphenyllithium onto the corresponding isatins.

However, the preparation of the corresponding3-hydroxy-3-(1,3,5-triazin-2-yl)-1,3-dihydro-2H-indol-2-ones isindustrially unviable because preparation and conversion of thetriazinyl Grignard compounds required as reactants, or of thetriazinyllithium compounds, are difficult under industrial conditions.

The conditions described in J. Chemical Soc., 1959, 2366 for oxidation,which is performed in the presence of a large excess of aqueous sodiumhydroxide solution at 90° C. to 95° C., are unsuitable for theconversion of 3-(1,3,5-triazin-2-yl)-1,3-dihydro-2H-indol-2-ones due tothe temperature, since the triazine ring would be cleavedhydrolytically. The yield is 60%.

However, it is not clear from these examples whether, under theconditions described for preparation of(2-aminophenyl)(phenyl)methanones, oxidative ring opening of1,3-dihydro-2H-indol-2-ones having a 6-membered heterocyclic ring,especially a triazine, in the 3 position in place of the phenyl ringwould also be possible to give the corresponding(2-aminophenyl)carbonyltriazines. It is also unclear whether thereaction is performable in an economically viable manner on theindustrial scale too.

SUMMARY

Against this background it is an object of the invention to provide analternative process for preparing 2-(triazinylcarbonyl)sulfonanilides onthe industrial scale, i.e. to provide a process for industrialproduction of 2-(triazinylcarbonyl)sulfonanilides with a very simpleprocess regime and maximum yields.

The object is achieved by a process for preparing2-(triazinylcarbonyl)sulfonanilides of the formula (1-1)

in which

-   R^(1a) to R^(1d) are each independently selected from the group    consisting of hydrogen, fluorine, chlorine, bromine, iodine and from-   (C₁-C₆)-alkyl where the alkyl radical is branched or unbranched and    is unsubstituted or substituted by one or more substituents selected    from the group consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkoxy where the alkoxy radical is branched or unbranched    and is unsubstituted or substituted by one or more substituents    selected from the group consisting of fluorine, chlorine,    (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkoxy where the cycloalkoxy radical is unsubstituted    or substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkylthio where the alkylthio radical is branched or    unbranched and is unsubstituted or substituted by one or more    substituents selected from the group consisting of fluorine,    chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₃-C₇)-cycloalkylthio where the cycloalkylthio radical is    unsubstituted or substituted by one or more substituents selected    from the group consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₁-C₄)-alkoxy, and-   phenyl or 1-naphthyl or 2-naphthyl or a five- or six-membered    heteroaromatic ring having 1 to 2 heteroatoms, where the heteroatoms    are each selected independently from the group consisting of O and    N, and where the aryl or heteroaryl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, bromine, iodine, (C₁-C₄)-alkyl,    (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkylthio, and-   R² is    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or fully        or partly substituted by fluorine, or    -   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted        or fully or partly substituted by fluorine,    -   and-   R⁴ and R⁵ are each hydrogen,    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or        substituted by one or more substituents selected from fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl, or    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,        which comprises    -   using as the reactant an N-sulfonyl-substituted        3-triazinyloxindole of the formula (2-1)

in which

-   R^(1a) to R^(1d) and R², R⁴ and R⁵ are each as defined in formula    (1-1), and-   R³ is hydrogen-   and    -   converting the reactant of the general formula (2-1) initially        charged in a solvent in the presence        -   of a base and        -   of an oxidizing agent.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The core idea of the process according to the invention for preparationof compounds of the formula (1-1) relates to the selection of anoxindole, especially of an N-sulfonyl-substituted 3-triazinyloxindole ofthe formula (2-1), as a reactant and in the conversion thereof byoxidative ring opening.

The reactant initially charged in a suitable solvent is firstdeprotonated with a suitable base. After addition of the oxidizingagent, the desired oxidative ring opening of compounds of the formula(2-1) takes place to give compounds of the formula (1-1).

The preparation of the N-sulfonyl-substituted 3-triazinyloxindoles ofthe formula (2-1) used as reactants on the industrial scale is describedin patent application EP 111598751.

Particular preference is given to the preparation of2-(triazinylcarbonyl)sulfonanilides of the formula (1-1) where

-   R^(1a) to R^(1d) are each independently selected from the group    consisting of hydrogen, fluorine, chlorine, bromine, iodine and from-   (C₁-C₆)-alkyl where the alkyl radical is branched or unbranched and    is unsubstituted or substituted by one or more substituents selected    from the group consisting of fluorine, chlorine, (C₁-C₄)-alkoxy or    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl or    (C₃-C₇)-cycloalkyl or (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkoxy where the alkoxy radical is branched or unbranched    and is unsubstituted or substituted by one or more substituents    selected from the group consisting of fluorine, chlorine,    (C₁-C₄)-alkoxy or (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkoxy where the cycloalkoxy radical is unsubstituted    or substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl or (C₁-C₄)-alkoxy,    and-   R² is (C₁-C₆)-alkyl where the alkyl radical is fully or partly    substituted by fluorine, and-   R³ is as defined in claim 1, and-   R⁴ and R⁵ are each independently    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy or (C₃-C₇)-cycloalkyl.

Very particular preference is given to the preparation of2-(triazinylcarbonyl)sulfonanilides of the formula (1-1), where

R^(1a) to R^(1d) are each independently selected from the groupconsisting of hydrogen, fluorine, chlorine, methoxy and

R² is difluoromethyl and R³ is hydrogen, and R⁴ and R⁵ are each methoxy.

With regard to the inventive compounds, the designations used above andbelow will be explained collectively. These are familiar to the personskilled in the art and have, more particularly, the definitionsexplained hereinafter:

The term “halogen” means, for example, fluorine, chlorine, bromine oriodine. If the term is used for a radical, “halogen” means, for example,a fluorine, chlorine, bromine or iodine atom.

Alkyl is a straight-chain or branched open-chain saturated hydrocarbylradical.

The expression “(C₁-C₄)alkyl” is a brief notation for alkyl having oneto four carbon atoms, according to the range stated for carbon atoms,which means that it includes the methyl, ethyl, 1-propyl, 2-propyl,1-butyl, 2-butyl, 2-methylpropyl or tert-butyl radicals. General alkylradicals having a greater specified range of carbon atoms, e.g.“(C₁-C₆)alkyl”, correspondingly also include straight-chain or branchedalkyl radicals having a greater number of carbon atoms, i.e. accordingto the example also the alkyl radicals having 5 and 6 carbon atoms.

Cycloalkyl is a carbocyclic saturated ring system having preferably 3-8ring carbon atoms, e.g. cyclopropyl, cyclobutyl, cyclopentyl orcyclohexyl. In the case of optionally substituted cycloalkyl, cyclicsystems with substituents are included, also including substituents witha double bond on the cycloalkyl radical, for example an alkylidene groupsuch as methylidene.

In the case of optionally substituted cycloalkyl, polycyclic aliphaticsystems are also included, for example bicyclo[1.1.0]butan-1-yl,bicyclo[1.1.0]butan-2-yl, bicyclo[2.1.0]pentan-1-yl,bicyclo[2.1.0]pentan-2-yl, bicyclo[2.1.0]pentan-5-yl,bicyclo[2.2.1]hept-2-yl(norbornyl), adamantan-1-yl and adamantan-2-yl.

In the case of substituted cycloalkyl, spirocyclic aliphatic systems arealso included, for example spiro[2.2]pent-1-yl, spiro[2.3]hex-1-yl,spiro[2.3]hex-4-yl, 3-spiro[2.3]hex-5-yl.

Aryl is a mono-, bi- or polycyclic aromatic system having preferably 6to 14 and especially 6 to 10 ring carbon atoms, for example phenyl,naphthyl, anthryl, phenanthrenyl, and the like, preferably phenyl.

The term “optionally substituted aryl” also includes polycyclic systems,such as tetrahydronaphthyl, indenyl, indanyl, fluorenyl, biphenylyl,where the bonding site is on the aromatic system.

In systematic terms, aryl is generally also encompassed by the term“optionally substituted phenyl”.

Alkoxy is an alkyl radical bonded via an oxygen atom, alkenyloxy is analkenyl radical bonded via an oxygen atom, alkynyloxy is an alkynylradical bonded via an oxygen atom, cycloalkyloxy is a cycloalkyl radicalbonded via an oxygen atom, and cycloalkenyloxy is a cycloalkenyl radicalbonded via an oxygen atom.

Alkylthio is an alkyl radical bonded via a sulfur atom, alkenylthio isan alkenyl radical bonded via a sulfur atom, alkynylthio is an alkynylradical bonded via a sulfur atom, cycloalkylthio is a cycloalkyl radicalbonded via a sulfur atom, and cycloalkenylthio is a cycloalkenyl radicalbonded via a sulfur atom.

Haloalkyl, -alkenyl and -alkynyl are, respectively, alkyl, alkenyl andalkynyl partly or fully substituted by identical or different halogenatoms, for example monohaloalkyl such as CH₂CH₂Cl, CH₂CH₂F, CHClCH₃,CHFCH₃, CH₂Cl, CH₂F; perhaloalkyl such as CCl₃ or CF₃ or CF₂CF₃;polyhaloalkyl such as CHF₂, CH₂F, CH₂CHFCl, CHCl₂, CF₂CF₂H, CH₂CF₃;haloalkoxy is, for example, OCF₃, OCHF₂, OCH₂F, OCF₂CF₃, OCH₂CF₃ andOCH₂CH₂Cl; the same applies to haloalkenyl and other halogen-substitutedradicals.

The definition “substituted by one or more radicals” means, unlessdefined otherwise, independently one or more identical or differentradicals, where two or more radicals on one cycle as a base structuremay form one or more rings.

Substituted radicals, such as a substituted alkyl, cycloalkyl,cycloalkenyl, aryl, phenyl, benzyl, heterocyclyl and heteroaryl radical,are, for example, a substituted radical derived from the unsubstitutedbase structure, where the substituents are, for example, one or more,preferably 1, 2 or 3, radicals from the group of halogen, alkoxy,alkylthio, hydroxyl, amino, nitro, carboxyl or a group equivalent to thecarboxyl group, isocyano, azido, alkoxycarbonyl, alkylcarbonyl, formyl,carbamoyl, mono- and dialkylaminocarbonyl, substituted amino, such asacylamino, mono- and dialkylamino, trialkylsilyl and optionallysubstituted cycloalkyl, optionally substituted aryl, optionallysubstituted heterocyclyl, where each of the latter cyclic groups mayalso be bonded via heteroatoms or divalent functional groups as in thealkyl radicals mentioned, and alkylsulfinyl, including both erastiomersof the alkylsulfinyl group, alkylsulfonyl, alkylphosphinyl,alkylphosphonyl and, in the case of cyclic radicals (=“cyclic basestructures”), also alkyl, haloalkyl, alkylthioalkyl, alkoxyalkyl,optionally substituted mono- and dialkylaminoalkyl, and hydroxyalkyl.

The term “substituted radicals”, such as substituted alkyl etc.,includes, as substituents, as well as the saturated hydrocarbonaceousradicals mentioned, corresponding unsaturated aliphatic and aromaticradicals, such as optionally substituted alkenyl, alkynyl, alkenyloxy,alkynyloxy, alkenylthio, alkynylthio, alkenyloxycarbonyl,alkynyloxycarbonyl, alkenylcarbonyl, alkynylcarbonyl, mono- anddialkenylaminocarbonyl, mono- and dialkynylaminocarbonyl, mono- anddialkenylamino, mono- and dialkynylamino, trialkenylsilyl,trialkynylsilyl, optionally substituted cycloalkenyl, optionallysubstituted cycloalkynyl, phenyl, phenoxy etc. In the case ofsubstituted cyclic radicals with aliphatic components in the ring,cyclic systems with those substituents which are bonded by a double bondto the ring are also included, for example by alkylidene group such asmethylidene or ethylidene, or an oxo group, imino group or substitutedimino group.

Each of the unsubstituted or substituted radicals may be branched andunbranched. For example, a radical designated “C₄-alkyl” comprises, aswell as the unbranched butyl radical, all other C₄ isomers, includingtert-butyl.

When two or more radicals form one or more rings, these may becarbocyclic, heterocyclic, saturated, partly saturated, unsaturated, forexample also aromatic and optionally further-substituted. The fusedrings are preferably 5- or 6-membered rings, particular preference beinggiven to benzofused cycles.

In a preferred embodiment of the process, the use of a heavy metalcatalyst which has at least one heavy metal or the salt of a heavy metalas constituent is envisaged for particularly efficient performance ofthe oxidative ring opening on the compounds of the formula (2-1)selected as the reactant. Suitable heavy metals are vanadium, chromium,manganese, iron, cobalt, nickel, copper, zinc, tin, antimony, bismuth,silver, gold, tungsten, ruthenium and/or osmium.

Advantageously, the effect of the heavy metal catalyst is to reduce thelevel of unwanted by-products and thus to enable the product yield ofthe reaction to be increased.

For instance, in the oxidation of the N-sulfonyl-substituted3-triazinyloxindoles of the formula (2-1) shown in scheme 6b below withaqueous solutions of hydrogen peroxide, it was found that, if nocatalyst is used, as well as the ketone of the formula (1-1) desired asthe product, a large proportion of the alcohol of the formula (3-1) isdisadvantageously also formed as a by-product.

The formation of alcohols of the formula (3-1), which do not reactfurther to give the ketone of the formula (1-1) under the reactionconditions, leads to yield losses and is therefore disadvantageous.

It is not clear from the prior art cited above regarding oxidative ringopening of 3-phenyl-1,3-dihydro-2H-indol-2-ones that the oxidative ringopening of N-sulfonyl-substituted 3-triazinyloxindoles (2-1) by hydrogenperoxide does in fact lead to partial formation of alcohols of theformula (3-1) (see scheme 6b). Nor can any technical teaching regardingthe avoidance of disadvantageous alcohol formation be found in the priorart.

For evidence of unwanted by-product formation, in the form ofcomparative synthesis example 1 variant C (see EXAMPLES), the oxidationof an N-sulfonyl-substituted 3-triazinyloxindole with an aqueoussolution of hydrogen peroxide was performed without addition of acatalyst. The product obtained is a mixture which, according to HPLCanalysis (area percent), consists to an extent of approx. 13% of theketone and to an extent of approx. 76% of the alcohol. This ratio ofketone to alcohol was also confirmed by NMR.

It has now been found that, interestingly, the formation of alcohols ofthe formula (3-1) can be substantially or almost completely suppressedwhen the oxidation is performed with hydrogen peroxide in the presenceof heavy metal salts, especially in the presence of iron salts.

Advantageously, the process allows the preparation of2-(triazinylcarbonyl)sulfonanilides on the industrial scale with a verysimple process regime, and the achievement of high yields of the desiredketone compound by the controlled avoidance of unwanted side reactions,which results in the formulation of unwanted alcohol compounds insteadof the desired ketones.

In principle, an oxidative ring opening can be brought about by amultitude of oxidizing agents. In the context of the present invention,i.e. in the oxidative ring opening of oxindoles, the use of theoxidizing agent in conjunction with a catalyst has been found to beparticularly advantageous.

The preferred oxidizing agent for the present invention is hydrogenperoxide in conjunction with a catalyst which has at least one heavymetal or the salt of a heavy metal as a constituent. Very particularpreference is given to the use of an aqueous hydrogen peroxide solutionin conjunction with a catalyst which has at least one heavy metal or thesalt of a heavy metal as a constituent.

A further preferred oxidizing agent is potassium permanganate. This canbe used alone or in conjunction with a catalyst which has at least oneheavy metal or the salt of a heavy metal as a constituent.

The catalysts or catalyst systems used are preferably the heavy metalsalts, heavy metal powders specified hereinafter, namely

-   -   iron salts such as iron(II) sulfate, iron chloride, and    -   iron powder, and    -   copper salts such as copper(II) sulfate, copper(II) chloride,        and    -   copper powder, and    -   mixtures of at least two of the aforementioned catalysts.

In order to increase the stability of the metal catalyst, one or morecomplexing substances can be added to the metal powder or the metal saltin each case, for example pyridine-2-carboxylic acid. Preference isgiven to

-   -   mixtures of iron salts with complexing compounds, for example        pyridine-2-carboxylic acid, and    -   mixtures of copper salts with complexing compounds, for example        pyridine-2-carboxylic acid, or    -   mixtures of at least two of the aforementioned catalyst systems.

Particularly preferred iron salts are iron(II) sulfate or iron chloride,or mixtures of the two salts. Very particularly preferred copper saltsare copper(II) sulfate or copper(II) chloride, or mixtures of the twosalts.

A particularly preferred complexing compound is pyridine-2-carboxylicacid.

A most preferred catalyst system is a mixture consisting of iron(II)sulfate and pyridine-2-carboxylic acid.

With regard to this most preferred embodiment, reference is made by wayof example to synthesis example 1 variant A, in which the oxidation ofan N-sulfonyl-substituted 3-triazinyloxindole with aqueous solution ofhydrogen peroxide is performed with addition of iron sulfate andpyridine-2-carboxylic acid as a catalyst system. TheN-sulfonyl-substituted 3-triazinyloxindole used as the reactant isidentical to the reactant used in synthesis example 1 variant C. Theketone corresponding to the formula (1-1) is obtained in a yield of 90%.No alcohol of the formula (3-1) as an unwanted by-product could bedetected.

The solvents used are preferably organic solvents which are entirely orpartly water-miscible. Organic solvents which are entirely or partlywater-miscible are

-   -   nitriles, especially acetonitrile, or    -   alcohols, especially 2-propanol, or    -   ketones, especially acetone.

The organic solvents mentioned are preferably used in a mixture withwater.

Particular preference is given to the performance of the process with amixture of acetonitrile and water as a solvent, or with a mixture of2-propanol and water.

Very particular preference is given to the performance of the processwith a solvent mixture composed of acetonitrile and water, in which theratio of acetonitrile and water is in the range of 2:1 to 1:2.

If hydrogen peroxide is used as the oxidizing agent, the formation ofacetone peroxides has to be expected when acetone is used as thesolvent. The formation of acetone peroxide is disadvantageous fortechnical reasons. However, the disadvantage mentioned need notnecessarily apply to all acetones usable as solvents.

The process is performed in the presence of a base. The base bringsabout complete or partial deprotonation of the N-sulfonyl-substituted3-triazinyloxindoles used as the reactant. Because the reactants afterthe deprotonation are present in the more reactive enolate form, the useof bases bring about a faster reaction overall.

Preference is given to using the following bases:

-   -   potassium carbonate, sodium carbonate or cesium carbonate, and    -   potassium hydrogencarbonate or sodium hydrogencarbonate, and    -   lithium hydroxide, sodium hydroxide, potassium hydroxide or        barium hydroxide, and    -   potassium phosphate (K₃PO₄), potassium hydrogenphosphate        (K₂HPO₄) or sodium phosphate.

It is within the scope of the invention that the bases used are alsoammonium hydroxides of the formula N(R¹⁰)₄OH with tetrasubstitution onthe nitrogen, in which the R¹⁰ radicals are each independently selectedfrom the group consisting of (C₁-C₆)-alkyl, where the alkyl radical isbranched or unbranched, and benzyl.

Particularly preferred bases are potassium carbonate or potassiumhydrogencarbonate, each of which is used alone or in a mixture.

The base is used either alone or as a mixture of several bases, in anequimolar amount or in excess (1.0 to 2.5 equivalents, preferably 1.0 to1.2 equivalents).

The oxidizing agent is also used in an equimolar amount or in excess (1to 7 equivalents, preferably 2 to 3 equivalents).

The catalyst is used in an equimolar amount or in deficiency (0.0001 to0.5 equivalent, preferably 0.001 to 0.01 equivalent).

The reactants can be added in one portion or in several portions over aperiod of up to 24 hours, preferably up to 6 hours, especially 0.05 to 6hours. After addition of individual reactants, a continued stirring time(0.1 to 12 hours, preferably 0.5 to 3 hours) may be advantageous.

The reaction temperature of the oxidation is in the range from −20° C.to 60° C., preferably in the range from 10° C. to 40° C. Thedeprotonation of the reactant of the formula (2) can be performed at thesame temperature as, or a different temperature than, the oxidation.

The reaction can optionally be performed under pressure.

For performance, it is advantageous when the N-sulfonyl-substituted3-triazinyloxindole is first initially charged with the base (totalamount or portion) in a suitable solvent, and then the catalyst andoptionally a further amount of the same or another base or of a mixtureof different bases is added in one or more portions, before theoxidizing agent is added.

One addition variant consists, in the case of use of potassiumpermanganate as an oxidizing agent in initially charging the oxidizingagent and the base in a suitable solvent and then adding theN-sulfonyl-substituted 3-triazinyloxindole, either in substance ordissolved or suspended in one of the solvents mentioned, in one or moreportions. Alternatively, the base can also be added in one or moreportions to the initially charged N-sulfonyl-substituted3-triazinyloxindole and the oxidizing agent.

It is within the scope of the invention that the N-sulfonyl-substituted3-triazinyloxindole is added to the reaction mixture as a salt. In thiscase, it is optionally possible to use less base.

The N-sulfonyl-substituted 3-triazinyloxindole and the base can be addedto the reaction mixture either in pure form or premixed with oneanother, or dissolved or suspended in a solvent or a solvent mixture. Itis possible that further solvent is added in the course of the reactionin order to enable better mixing of the reactants.

Depending on the reaction conditions used, the continued stirring timeafter addition of all reactants is in the range of up to 96 hours,preferably 0.05 to 24 hours.

The workup and isolation of the desired product of the formula (1) canbe effected in various ways, and depends, for example, on the selectionof the solvent or depends on whether the product is a solid or a liquid.

The reaction mixture which comprises a solid product of the formula (1)or (1-1) is filtered. The solid product thus obtained can be washed withsuitable solvents and/or aqueous acids.

It is additionally envisaged that another, higher-boiling solvent inwhich the product is more sparingly soluble is added to the reactionmixture comprising product of the general formula (1-1), and thelower-boiling solvent is distilled off completely or partially.Subsequently, the product in solid form is filtered off and can bewashed with suitable solvents and/or aqueous acids.

It is also within the scope of the invention that the product obtainedafter filtration and optional washing is extracted by stirring from asuitable solvent or a mixture of several solvents, in order to obtainthe product in a higher purity.

Another means of workup consists in the extraction of the reactionmixture with a suitable solvent, from which the product is subsequentlyisolated.

The products of the formula (1-1) can be isolated either as freesulfonanilides (i.e. compounds protonated on the sulfonanilide nitrogen)or as salts (i.e. compounds deprotonated on the sulfonanilide nitrogenand having a cationic counterion). The salts may comprise potassium,sodium, cesium, lithium, barium or tetraalkylammonium as suitablecationic counterions.

It is likewise envisaged that the products of the formula (1-1) presentin the reaction mixture, or the salts, can be converted further toconversion products without preceeding isolation.

More particularly, the products of the formula (1-1) present in thereaction mixture, or the salts, can be converted with or withoutisolation to give conversion products by alkylation on the sulfonanilidenitrogen to giveN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides.

The N-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamidesof the general formula (4-1) thus obtainable

have been demonstrated to have herbicidal activity (WO 2007/031208 A2)and fungicidal activity (WO 2006/008159 A1).

ObtainingN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides ofthe general formula (4-1) proceeding from N-sulfonyl-substituted3-triazinyloxindoles of the formula (2-1) is economically advantageouscompared to known synthesis routes.

The present invention therefore also provides for the use ofN-sulfonyl-substituted 3-triazinyloxindoles of the formula (2-1)

-   -   or salts thereof (2-1a)

-   -   in each of which    -   R^(1a) to R^(1d) are each independently selected from the group        consisting of hydrogen, fluorine, chlorine, bromine, iodine and        from    -   (C₁-C₆)-alkyl where the alkyl radical is branched or unbranched        and is unsubstituted or substituted by one or more substituents        selected from the group consisting of fluorine, chlorine,        (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,    -   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted        or substituted by one or more substituents selected from the        group consisting of fluorine, chlorine, (C₁-C₄)-alkyl and        (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkoxy,    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,    -   (C₃-C₇)-cycloalkoxy where the cycloalkoxy radical is        unsubstituted or substituted by one or more substituents        selected from the group consisting of fluorine, chlorine,        (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,    -   (C₁-C₆)-alkylthio where the alkylthio radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,    -   (C₃-C₇)-cycloalkylthio where the cycloalkylthio radical is        unsubstituted or substituted by one or more substituents        selected from the group consisting of fluorine, chlorine,        (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy and    -   phenyl or 1-naphthyl or 2-naphthyl or a five- or six-membered        heteroaromatic ring having 1 to 2 heteroatoms, where the        heteroatoms are each selected independently from the group        consisting of O and N, and where the aryl or heteroaryl radical        is unsubstituted or substituted by one or more substituents        selected from the group consisting of fluorine, chlorine,        bromine, iodine, (C₁-C₄)-alkyl, (C₁-C₄)-alkoxy and        (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkylthio, and    -   R² is    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or fully        or partly substituted by fluorine, or    -   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted        or fully or partly substituted by fluorine,    -   R³ is hydrogen, and    -   R⁴ and R⁵ are each hydrogen,    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or        substituted by one or more substituents selected from the group        consisting of fluorine, chlorine, (C₁-C₄)-alkoxy or        (C₃-C₇)-cycloalkyl,    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,    -   wherein M in the salts of the general formula (2-1a) is Li, Na,        K, Cs, Ba, Mg, Ca, Zn or N(R^(c))₄ in which R^(c)═H or        (C₁-C₆)-alkyl or benzyl, and    -   where the number of counterions M⁺ is guided by the particular        charge, such    -   that the compound of the general formula (2-1a) is uncharged        overall, as reactants or as intermediates for the synthesis of        active ingredients in the agricultural sector.

Particular preference is given to the use of N-sulfonyl-substituted3-triazinyloxindoles of the formula (2-1) or salts of the formula(2-1a), where

R^(1a) to R^(1d) are each independently selected from the groupconsisting of hydrogen, fluorine, chlorine, and from

(C₁-C₆)-alkyl where the alkyl radical is branched or unbranched,

(C₁-C₆)-alkoxy where the alkoxy radical is branched or unbranched, and

R² is methyl, where the methyl is fully or partly substituted byfluorine, or

(C₃-C₇)-cycloalkyl where the cycloalkyl radical is fully or partlysubstituted by fluorine,

R³ is hydrogen, and

R⁴ and R⁵ are each independently

(C₁-C₄)-alkyl where the alkyl radical is branched or unbranched,

(C₁-C₄)-alkoxy where the alkoxy radical is branched or unbranched,

where M in the salts of the general formula (2-1a) is Na and K, asintermediates for the synthesis of active ingredients in theagricultural sector.

Very particular preference is given to the use of N-sulfonyl-substituted3-triazinyloxindoles of the formula (2-1) or salts of the formula(2-1a), where

R^(1a) to R^(1d) are each independently selected from the group

-   -   consisting of hydrogen, fluorine, chlorine, methoxy, and        R² is difluoromethyl or trifluoromethyl,        R³ is hydrogen, and        R⁴ and R⁵ are each independently methoxy, as intermediates for        the synthesis of active ingredients in the agricultural sector.

Most preferred is the use of N-sulfonyl-substituted 3-triazinyloxindolesof the formula (2-1) or salts of the formula (2-1a), where R^(1a) toR^(1d) are each independently selected from the group consisting ofhydrogen and fluorine, R² is difluoromethyl, R³ is hydrogen, and R⁴ andR⁵ are each independently methoxy, as intermediates for the synthesis ofactive ingredients in the agricultural sector.

The above-described oxidation process for preparing compounds of thegeneral formula (1-1) is characterized by the mechanism of oxidativering opening, and is thus based on the selection of oxindoles asreactants, since these are amenable to oxidative ring opening.

The selection of compounds with oxindole structure as reactants, orintermediates, also characterizes a multistage process for preparingcompounds of the general formula (1-1) and, proceeding therefrom,compounds of the general formula (4-1), which are known to be notablefor herbicidal and fungicidal action.

The above-described oxidation process, which is based on the oxidativering opening of oxindole compounds of the general formula (2-1), forpreparing compounds of the general formula (1-1) is a component step ofthe multistage process described in scheme 7.

The oxindole compounds used as reactants, or intermediates, in themultistage process are summarized in scheme 7 below, and designated withthe general formulae (7-1), (6-1), (5-1) and (2-1).

The multistage process shown in scheme 7 is notable, compared to thepreviously known processes for preparingN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]-alkanesulfonamides(4-1) and 2-(triazinylcarbonyl)sulfonanilides (1-1), in that oxindolecompounds are used as reactants, or as intermediates. This brings theadvantage that the process, as compared with the previously knownprocesses, can be performed on the industrial scale, and high yields canbe obtained at the same time.

The execution of the process summarized in scheme 7 is explainedhereinafter. The reduction, which in scheme 7 relates to the firstreaction step of the overall five-stage process, is treated here as anindependent preliminary stage B).

The other reaction steps summarized in scheme 7, i.e. the steps ofarylation, sulfonylation, oxidation and alkylation, are referred tocollectively hereinafter as process A).

A) A process for preparingN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides ofthe formula (4-1)

in which

-   R^(1a) to R^(1d) are each independently selected from the group    consisting of hydrogen, fluorine, chlorine, bromine, iodine and from-   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkoxy where the alkoxy radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkoxy where the cycloalkoxy radical is unsubstituted    or substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkylthio where the alkylthio radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₃-C₇)-cycloalkylthio where the cycloalkylthio radical is    unsubstituted or substituted by one or more substituents selected    from the group consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₁-C₄)-alkoxy and-   phenyl or 1-naphthyl or 2-naphthyl or a five- or six-membered    heteroaromatic ring having 1 to 2 heteroatoms, where the heteroatoms    are each selected independently from the group consisting of O and    N, and where the aryl or heteroaryl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, bromine, iodine, (C₁-C₄)-alkyl,    (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkylthio, and-   R² is    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or fully        or partly substituted by fluorine, or    -   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted        or fully or partly substituted by fluorine,-   R⁴ and R⁵ are each independently    -   hydrogen,    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or        substituted by one or more substituents selected from the group        consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and        (C₃-C₇)-cycloalkyl,    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,    -   and-   R⁸ is    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or partly        or fully substituted by fluorine,    -   (C₁-C₆)-cycloalkyl, (C₁-C₆)-alkenyl or (C₁-C₆)-alkoxyalkyl,        where each of the radicals mentioned is unsubstituted or        substituted partly or fully by fluorine,    -   wherein-   a 1,3-dihydro-2H-indol-2-one of the formula (6-1)

in which

-   R^(1a) to R^(1d) are each as defined for formula (4-1),-   R³ is hydrogen, and-   R⁷ is hydrogen, is converted in a    first step by    -   arylation to give a triazinyl-substituted oxindole of the        formula (5-1)

in which

-   -   R^(1a) to R^(1d) and R⁴ and R⁵ are each as defined for the        formula (4-1) and R³ and    -   R⁷ are each as defined for the formula (6-1),    -   and the arylation products of the formula (5-1) are converted in        a        second step by    -   sulfonylation to give N-sulfonyl-substituted        3-triazinyloxindoles of the formula (2-1)

in which

-   -   R^(1a) to R^(1d), R² and R⁴ and R⁵ are each as defined in        formula (4-1) and R³ is as defined for formula (6-1),    -   and the sulfonylation products of the formula (2-1) are        converted in a        third step by    -   oxidative ring opening to give a        2-(triazinylcarbonyl)sulfonanilide of the formula (1-1)

in which

-   -   R^(1a) to R^(1d), R² and R⁴ and R⁵ are each as defined for        formula (4-1),    -   and the oxidation products of the formula (1-1) are converted in        a        fourth step by    -   alkylation to give an        N-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamide        of the formula (4-1)

in which

-   -   R^(1a) to R^(1d), R², R⁴, R⁵ and R⁸ are each as defined for        formula (4-1),    -   wherein the alkylating reagent used is        -   X—R⁸, where X is chlorine, bromine or iodine and R⁸ is as            defined above for formula (4-1), or        -   (R⁸)₂SO₄, in which R⁸ is as defined above for formula (4-1).

The process A) for preparing N-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides of the formula (4-1) consists of fourcomponent steps which, with the exception of the oxidation—the subjectmatter of the present invention—are the subject matter of priorapplications:

-   -   Arylation of substituted or unsubstituted        1,3-dihydro-2H-indol-2-ones (6-1) to triazinyl-substituted        oxindoles (5-1). This process is possible on the industrial        scale and is described in patent application EP 10196205.8. With        regard to the practicability of the arylation, reference is made        here to the content of patent application EP 10196205.8.    -   Sulfonylation of triazinyl-substituted oxindoles (5-1) to        N-sulfonyl-substituted 3-triazinyloxindoles (2-1). This process        is possible on the industrial scale and is described in patent        application EP 11159875.1. With regard to the practicability of        the sulfonylation, reference is made here to the contents of        patent application EP 11159875.1.    -   Oxidative ring opening of N-sulfonyl-substituted        3-triazinyloxindoles (2-1) to        2-(triazinylcarbonyl)sulfonanilides (1-1). This process is        possible on the industrial scale and forms part of the subject        matter of the present invention.    -   Alkylation of 2-(triazinylcarbonyl)sulfonanilides (1-1) to        N-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides        (4-1). This process is described in patent application WO        2006/008159 A1. With regard to the practicability of the        alkylation, reference is made here to the contents of patent        application WO 2006/008159 A1.

The arylation is performed in the presence

-   -   of a carbonate, or    -   of a hydroxide, or    -   of a phosphate, or    -   in a mixture comprising at least two of the aforementioned        bases.

Preferably, in the arylation, the bases used are potassium carbonate,sodium carbonate, sodium hydroxide, potassium hydroxide, or an at leasttwo-component mixture consisting of at least one of the two carbonates:potassium carbonate and sodium carbonate, and of at least one of the twohydroxides: potassium hydroxide and sodium hydroxide.

The sulfonylation is performed in the presence

-   -   of a 1-substituted imidazole base, or    -   of a base mixture comprising at least one 1-substituted        imidazole base.

Particularly preferred imidazole bases for the performance of thesulfonylation are 1-methyl-1H-imidazole, 1-butyl-1H-imidazole or1-benzyl-1H-imidazole, which can be used individually or in a mixture,very particular preference being given to the use of1-methyl-1H-imidazole.

The alkylation can be effected with standard alkylating agents. In thecase of a methylation, preference is given to using dimethyl sulfate.

The herbicidal action (see WO 2007/031208 A2) and fungicidal action (seeWO 2006/008159 A1) ofN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides ofthe formula (4-1) has been known for a long time.

Thus, the above details regarding the practicability of the reactionscombined in process A), consisting of arylation, sulfonylation,oxidation and alkylation, demonstrate the suitability of oxindoles ofthe formulae (6-1), (5-1), (2-1), and compounds of the formula (1-1),for preparation of crop protection agents of the formula (4-1).

B) The process for preparingN-alkyl-N-[2-(1,3,5-triazin-2-ylcarbonyl)phenyl]alkanesulfonamides ofthe formula (4-1), wherein the compounds of the formula (6-1) used asthe reactant are prepared in a preceding process step in whichconversion is effected proceeding from a3-(alkylsulfanyl)-1,3-dihydro-2H-indol-2-one of the formula (7-1)

in which

-   R^(1a) to R^(1d) are each as defined for formula (4-1),-   R³ is hydrogen,-   R⁷ is hydrogen, and-   R⁶ is an unsubstituted or substituted (C₁-C₁₄)-alkyl,    (C₃-C₇)-cycloalkyl, benzyl or a CH₂—C(O)O—(C₁-C₆)-alkyl,    by    -   reduction to give a 1,3-dihydro-2H-indol-2-one (6-1)

in which

-   -   R^(1a) to R^(1d), R³ and R⁷ are each as defined for formula        (7-1).

Process B) relates to the reduction of substituted or unsubstituted3-(alkylsulfanyl)-1,3-dihydro-2H-indol-2-ones (7-1) to substituted orunsubstituted 1,3-dihydro-2H-indol-2-ones (6-1). This process ispossible on the industrial scale and is described in patent applicationEP 10162381.7. With regard to the practicability of the reduction,reference is made here to the contents of patent application EP10162381.7.

In the reduction,

-   a) a compound of the formula (7-1) is dissolved or suspended in a    polar solvent,-   b) a sulfur-containing salt is added to the solution or suspension,    and-   c) the reaction mixture is heated under reflux at a temperature not    exceeding the boiling temperature of the polar solvent.

Particularly preferred sulfur-containing salts are sodium salts selectedfrom the group consisting of sodium bisulfite, sodium sulfite, sodiumthionite, sodium dithionite and sodium thiosulfate.

The invention also provides the 2-(triazinylcarbonyl)sulfonanilides ofthe formula (1-1) prepared by the oxidation process explained above,i.e. the oxidative ring opening of oxindole compounds of the formula(2-1),

in which

-   R^(1a) to R^(1d), R², R⁴ and R⁵ are each as defined for formula    (4-1), i.e.-   R^(1a) to R^(1d) are each independently selected from the group    consisting of hydrogen, fluorine, chlorine, bromine, iodine and from-   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkoxy where the alkoxy radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and    (C₃-C₇)-cycloalkyl,-   (C₃-C₇)-cycloalkoxy where the cycloalkoxy radical is unsubstituted    or substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₁-C₆)-alkylthio where the alkylthio radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,-   (C₃-C₇)-cycloalkylthio where the cycloalkylthio radical is    unsubstituted or substituted by one or more substituents selected    from the group consisting of fluorine, chlorine, (C₁-C₄)-alkyl and    (C₁-C₄)-alkoxy and-   phenyl or 1-naphthyl or 2-naphthyl or a five- or six-membered    heteroaromatic ring having 1 to 2 heteroatoms, where the heteroatoms    are each selected independently from the group consisting of O and    N, and where the aryl or heteroaryl radical is unsubstituted or    substituted by one or more substituents selected from the group    consisting of fluorine, chlorine, bromine, iodine, (C₁-C₄)-alkyl,    (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkylthio, and-   R² is    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or fully        or partly substituted by fluorine, or    -   (C₃-C₇)-cycloalkyl where the cycloalkyl radical is unsubstituted        or fully or partly substituted by fluorine,-   R⁴ and R⁵ are each independently    -   hydrogen,    -   (C₁-C₆)-alkyl where the alkyl radical is unsubstituted or        substituted by one or more substituents selected from the group        consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and        (C₃-C₇)-cycloalkyl,    -   (C₁-C₆)-alkoxy where the alkoxy radical is branched or        unbranched and is unsubstituted or substituted by one or more        substituents selected from the group consisting of fluorine,        chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl.

The aforementioned compounds of the formula (1-1) are importantintermediates in the process explained above for preparation ofherbicides or fungicides of the formula (4-1). The2-(triazinylcarbonyl)sulfonanilides of the formula (1-1) prepared byoxidative ring opening of oxindole compounds of the formula (2-1) andsubsequent alkylation likewise form part of the subject matter of theinvention.

The examples which follow illustrate the invention in detail, butwithout limiting the subject matter thereof to these examples.

In the examples which follow, stated amounts are based on weight, unlessspecifically defined otherwise. In the description, the abbreviation %by wt.=percent by weight was used analogously therefor. For units ofmeasurement, physical parameters and the like, customary abbreviationsare used, for example h=hour(s), m.p.=melting point, l=liter,ml=milliliter, g=gram, min=minute(s), in vacuo=under reduced pressure,of theory=percent theoretical yield, RT=room temperature,eq.=equivalents.

The coupling patterns in the NMR spectra are described as they appear.

Proportions on the basis of HPLC analysis are, unless stated otherwise,reported in relative area percentages.

Percentages in the LC-MS analysis relate to the relative proportion ofthe particular component in the chromatogram.

Example 1 Preparation ofN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamide

Variant A (Oxidation with Hydrogen Peroxide and Iron Sulfate inWater/Acetonitrile):1-[(Difluoromethyl)sulfonyl]-3-(4,6-dimethoxy-1,3,5-triazin-2-yl)-7-fluoro-1H-indol-2-ol(100 g) is initially charged in 330 ml of acetonitrile and thesuspension is heated to 35° C. A solution of potassium hydrogencarbonate(25.4 g) in 145 ml of water is added dropwise within 45 min. Iron(II)sulfate heptahydrate (395 mg) and pyridine-2-carboxylic acid (175 mg)are premixed in 1 ml of water and added to the mixture. Hydrogenperoxide (35% in water, 58 g) is added dropwise over 135 min, and theinternal temperature is kept at 25° C.-28° C. Stirring is continued for170 min, sodium sulfite (3 g) and potassium hydrogencarbonate (3 g) isadded, the mixture is concentrated to 282 g at 40° C. under reducedpressure, and the solid residue is filtered off. 2-Propanol (150 ml) isadded to the solution and the pH is adjusted to 2 with hydrochloricacid, such that a solid precipitates out. After adding 160 ml of water,the solid is filtered off, washed with 100 ml of 2-propanol/water (1:4)and 200 ml of water, and dried. This givesN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamidein a purity of 97% (86.2 g, 90% of theory).

LC-MS: M+H=393 (96%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=9.2 (broad s, 1H), 7.54 (d, 1H), 7.47(t, 1H), 7.34 (dt, 1H), 6.48 (t, 1H), 4.12 (s, 6H).

Variant B (Oxidation with Potassium Permanganate):

Potassium permanganate (184 mg) and potassium carbonate (96 mg) areinitially charged in 2 ml of a mixture of water and acetonitrile (1:1)at 0° C. While cooling,1-[(difluoromethyl)sulfonyl]-3-(4,6-dimethoxy-1,3,5-triazin-2-yl)-7-fluoro-1H-indol-2-ol(186 mg) is added as a solid in portions within 20 min, and the mixtureis stirred for a further 90 min. For workup, dilute sulfuric acid (20%in water, 2 ml) is added, the mixture is stirred briefly until the endof gas evolution, and the mixture is added dropwise to a solution ofsodium sulfite (10% in water, 3 ml). The organic solvent issubstantially removed under reduced pressure and the aqueous residue isextracted with dichloromethane. The organic phase is washed once with asolution of ammonium chloride in water and concentrated. This givesN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamidein an HPLC purity of >99% (123 mg, 72% of theory). The NMR correspondsto that of the product obtained in variant A.

Variant C (=Comparative Example 1C—Oxidation with Hydrogen Peroxidewithout Catalyst):

1-[(Difluoromethyl)sulfonyl]-3-(4,6-dimethoxy-1,3,5-triazin-2-yl)-7-fluoro-1H-indol-2-ol(60 g) is initially charged in 165 ml of acetonitrile and the suspensionis heated to 35° C. A solution of potassium hydrogencarbonate (14.8 g)in 74 ml of water is added dropwise and the mixture is heated to 35° C.within 30 min and stirred at 35° C. for a further 10 min. The mixture iscooled again to 25° C. and hydrogen peroxide (35% in water, 34 g) isadded dropwise within 4 hours, in the course of which the internaltemperature is kept at 25° C.-27° C. The result is a clear homogeneoussolution. The mixture is left to stand at 22° C. overnight. According toHPLC (210 nm, figures in area percent), 15% of the title compound and78% alcohol(N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(hydroxy)methyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamide)have formed. Sodium sulfite (18 g) and then potassium hydrogencarbonate(19 g) are added to the mixture in portions, and the mixture isconcentrated at 40° C. under reduced pressure, in the course of which168 ml of distillate are removed. Since isolation of the product mixtureas a filterable solid with 2-propanol is not possible as in example 1variant A, the mixture is made up to a volume of 1 l with water andcooled to 5° C., the pH is adjusted to 2 with hydrochloric acid, and theprecipitated solid is filtered off and washed with 11 of water. Thisgives 50.1 g of a mixture which, according to HPLC, consists of thetitle compound (14% area) and the alcoholN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(hydroxy)methyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamide(82% area). The yield is 13% of theory (title compound) and 76% oftheory (alcohol). The NMR of the mixture confirms the presence of titlecompound (approx. 12%) and alcohol (approx. 88%).

1H NMR (400 MHz, CDCl₃) ofN-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)(hydroxy)methyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamide:δ (ppm)=9.4 (broad s, 1H), 7.48 (d, 1H), 7.31 (dt, 1H), 7.14 (t, 1H),6.57 (t, 1H), 6.10 (s, 1H), 4.7 (broad s, 1H), 4.09 (s, 6H).

Synthesis examples 2 to 9 were performed by oxidation with hydrogenperoxide in acetonitrile/water in the presence of iron(II) sulfateheptahydrate and pyridine-2-carboxylic acid.

Example 2N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-4-methoxyphenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=405 (100%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=10.5 (broad s, 1H), 7.78 (d, 1H), 7.19(dd. 1H), 7.14 (d, 1H), 6.29 (t, 1H), 4.12 (s, 6H), 3.78 (s, 3H).

Example 3N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-4,6-difluorophenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=411 (91%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=8.2 (broad s, 1H), 7.35 (dd, 1H), 7.21(dt, 1H), 6.35 (t, 1H), 4.12 (s, 6H).

Example 4N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-methoxyphenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=405 (98%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=8.6 (broad s, 1H), 7.30-7.35 (m, 2H),7.24 (dd, 1H), 6.52 (t, 1H), 4.11 (s, 6H), 3.96 (s, 3H).

Example 5N-{2-[(4,6-diethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl}-1,1-difluoromethanesulfonamide

LC-MS: M−H=419 (100%).

1H NMR (600 MHz, CDCl₃): δ (ppm)=9.2 (broad s, 1H), 7.56 (d, 1H), 7.46(t, 1H), 7.35 (dt, 1H), 6.50 (t, 1H), 4.55 (q, 4H), 1.46 (t, 6H).

Example 61,1-difluoro-N-{2-fluoro-6-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)carbonyl]phenyl}methanesulfonamide

LC-MS: M+H=377 (100%).

1H NMR (600 MHz, CDCl₃): δ (ppm)=9.2 (broad s, 1H), 7.52 (d, 1H), 7.48(t, 1H), 7.36 (dt, 1H), 6.50 (t, 1H), 4.11 (s, 3H), 2.72 (s, 3H).

Example 7N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl}-1,1,1-trifluoromethanesulfonamide

LC-MS: M+H=411 (88%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=8.7 (broad s, 1H), 7.55 (dt, 1H),7.40-7.50 (m, 2H), 4.12 (s, 6H).

Example 8N-{2-chloro-6-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]phenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=409, 411 (100%).

1H NMR (400 MHz, DMSO-D₆): δ (ppm)=11.0 (broad s, 1H), 7.88 (dd, 1H),7.75 (dd, 1H), 7.58 (t, 1H), 6.93 (t, 1H), 3.96 (s, 6H).

Synthesis examples 9 and 10 were performed by oxidation with potassiumpermanganate in acetonitrile/water.

Example 9N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-4-fluorophenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=393 (96%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=10.8 (broad s, 1H), 7.87 (dd, 1H),7.34-7.42 (m, 2H), 6.33 (t, 1H), 4.13 (s, 6H).

Example 10N-{2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]phenyl}-1,1-difluoromethanesulfonamide

LC-MS: M+H=375 (90%).

1H NMR (400 MHz, CDCl₃): δ (ppm)=11.1 (broad s, 1H), 7.88 (d, 1H),7.61-7.68 (m, 2H), 7.18 (t, 1H), 6.34 (t, 1H), 4.12 (s, 6H).

The invention claimed is:
 1. A process for preparing a2-(triazinylcarbonyl)sulfonanilides of formula (1-1)

in which R^(1a) to R^(1d) are each independently selected from the groupconsisting of hydrogen, fluorine, chlorine, bromine, iodine and from(C₁-C₆)-alkyl where the alkyl radical is branched or unbranched and isunsubstituted or substituted by at least one substituent selected fromthe group consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and(C₃-C₇)-cycloalkyl, (C₃-C₇)-cycloalkyl where the cycloalkyl radical isunsubstituted or substituted by at least one substituent selected fromthe group consisting of fluorine, chlorine, (C₁-C₄)-alkyl and(C₃-C₇)-cycloalkyl and (C₁-C₄)-alkoxy, (C₁-C₆)-alkoxy where the alkoxyradical is branched or unbranched and is unsubstituted or substituted byat least one substituent selected from the group consisting of fluorine,chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl, (C₃-C₇)-cycloalkoxywhere the cycloalkoxy radical is unsubstituted or substituted by atleast one substituent selected from the group consisting of fluorine,chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy, (C₁-C₆)-alkylthio where thealkylthio radical is branched or unbranched and is unsubstituted orsubstituted by at least one substituent selected from the groupconsisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy,(C₃-C₇)-cycloalkylthio where the cycloalkylthio radical is unsubstitutedor substituted by at least one substituent selected from the groupconsisting of fluorine, chlorine, (C₁-C₄)-alkyl and (C₁-C₄)-alkoxy, andphenyl or 1-naphthyl or 2-naphthyl or a five- or six-memberedheteroaromatic ring having from 1 to 2 heteroatoms, where theheteroatoms are each selected independently from the group consisting ofO and N, and where the aryl or heteroaryl radical is unsubstituted orsubstituted by at least one substituent selected from the groupconsisting of fluorine, chlorine, bromine, iodine, (C₁-C₄)-alkyl,(C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl and (C₁-C₄)-alkylthio, and R² is(C₁-C₆)-alkyl where the alkyl radical is unsubstituted or fully orpartly substituted by fluorine, or (C₃-C₇)-cycloalkyl where thecycloalkyl radical is unsubstituted or fully or partly substituted byfluorine, and R⁴ and R⁵ are each hydrogen, (C₁-C₆)-alkyl where the alkylradical is unsubstituted or substituted by at least one substituentselected from fluorine, chlorine, (C₁-C₄)-alkoxy and (C₃-C₇)-cycloalkyl,or (C₁-C₆)-alkoxy where the alkoxy radical is branched or unbranched andis unsubstituted or substituted by at least one substituent selectedfrom the group consisting of fluorine, chlorine, (C₁-C₄)-alkoxy and(C₃-C₇)-cycloalkyl, which comprises using as a reactant anN-sulfonyl-substituted 3-triazinyloxindole of formula (2-1)

in which R^(1a) to R^(1d) and R², R⁴ and R⁵ are each as defined informula (1-1), and R³ is hydrogen and converting the reactant of formula(2-1) initially charged in a solvent in the presence of a base and of anoxidizing agent.
 2. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim1, where R^(1a) to R^(1d) are each independently selected from the groupconsisting of hydrogen, fluorine, chlorine, bromine, iodine and from(C₁-C₆)-alkyl where the alkyl radical is branched or unbranched and isunsubstituted or substituted by at least one substituent selected fromthe group consisting of fluorine, chlorine, (C₁-C₄)-alkoxy or(C₃-C₇)-cycloalkyl, (C₃-C₇)-cycloalkyl where the cycloalkyl radical isunsubstituted or substituted by at least one substituent selected fromthe group consisting of fluorine, chlorine, (C₁-C₄)-alkyl or(C₃-C₇)-cycloalkyl or (C₁-C₄)-alkoxy, (C₁-C₆)-alkoxy where the alkoxyradical is branched or unbranched and is unsubstituted or substituted byat least one substituent selected from the group consisting of fluorine,chlorine, (C₁-C₄)-alkoxy or (C₃-C₇)-cycloalkyl, (C₃-C₇)-cycloalkoxywhere the cycloalkoxy radical is unsubstituted or substituted by atleast one substituent selected from the group consisting of fluorine,chlorine, (C₁-C₄)-alkyl or (C₁-C₄)-alkoxy, and R² is (C₁-C₆)-alkyl wherethe alkyl radical is fully or partly substituted by fluorine, and R⁴ andR⁵ are each independently (C₁-C₆)-alkoxy where the alkoxy radical isbranched or unbranched and is unsubstituted or substituted by at leastone substituent selected from the group consisting of fluorine,chlorine, (C₁-C₄)-alkoxy or (C₃-C₇)-cycloalkyl.
 3. The process forpreparing a 2-(triazinylcarbonyl)sulfonanilide of formula (1-1)according to claim 1, where R^(1a) to R^(1d) are each independentlyselected from the group consisting of hydrogen, fluorine, chlorine,methoxy, and R² is difluoromethyl and R³ is hydrogen, and R⁴ and R⁵ areeach methoxy.
 4. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim1, wherein the oxidizing agent is used in combination with a catalystwhich has at least one heavy metal and/or a salt of a heavy metal as aconstituent.
 5. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim4, wherein said oxidizing agent used is hydrogen peroxide in conjunctionwith a catalyst which comprises at least one heavy metal and/or a saltof a heavy metal as a constituent.
 6. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim4, wherein said oxidizing agent used is potassium permanganate withoutor with a catalyst which comprises at least one heavy metal and/or asalt of a heavy metal as a constituent.
 7. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim4, wherein the catalyst used comprises at least one of: iron salts, ironpowder, copper salts or copper powder, or a mixture thereof.
 8. Theprocess for preparing a 2-(triazinylcarbonyl)sulfonanilide of formula(1-1) as claimed in claim 4, wherein the catalyst used comprises: atleast one iron salt together with at least one complexing compound, orat least one copper salt together with at least one complexing compound,or a mixture thereof.
 9. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim7, wherein said iron salt used comprises iron(II) sulfate and/or ironchloride, and said copper salts used comprises copper(II) sulfate and/orcopper(II) chloride.
 10. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim8, wherein said complexing compound used is pyridine-2-carboxylic acid.11. The process for preparing a 2-(triazinylcarbonyl)sulfonanilide offormula (1-1) as claimed in claim 9, wherein the catalyst used isiron(II) sulfate together with pyridine-2-carboxylic acid.
 12. Theprocess for preparing a 2-(triazinylcarbonyl)sulfonanilide of formula(1-1) as claimed in claim 1, wherein the solvent used is a mixturecomprising at least one water-miscible organic solvent and water. 13.The process for preparing a 2-(triazinylcarbonyl)sulfonanilide offormula (1-1) as claimed in claim 12, wherein said solvent used isacetonitrile and/or 2-propanol.
 14. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim1, wherein the base used is at least one of: potassium carbonate, sodiumcarbonate or cesium carbonate, potassium hydrogencarbonate or sodiumhydrogencarbonate, lithium hydroxide, sodium hydroxide, potassiumhydroxide or barium hydroxide, potassium phosphate (K₃PO₄), potassiumhydrogenphosphate (K₂HPO₄) or sodium phosphate, and/or a mixturethereof.
 15. The process for preparing a2-(triazinylcarbonyl)sulfonanilide of formula (1-1) as claimed in claim14, wherein said base used is potassium hydrogencarbonate or potassiumcarbonate or a mixture thereof.